In the gantry of a CT scanner air bearings are used to support the rotating parts of the gantry. Such a CT scanner is, for instance, disclosed in WO 2004/030542 A2, according to which a plurality of air bearing elements are interfacing a stationary gantry and a rotating gantry. To absorb vibrational energy and to damp air hammer vibrations a damping assembly is mounted to at least one lower bearing element.
Instead of air bearings it is also possible to use fluid bearings between the stationary gantry and the rotating gantry employing radial and axial fluid bearing pads, such as disclosed in WO 02/089671 A2. The fluid bearing provides a fluid barrier which separates the rotating gantry from the stationary gantry.
Those bearings are one of the major costly components in such a CT scanner and in other rotating ring apparatuses.